1. Field of the Invention
The invention relates to magneto-resistive (MR) heads, and more particularly to biasing a resistive element (RMR) of the MR head with constant power.
2. Description of the Related Art
A magneto-resistive (MR) head typically has a resistive element (RMR). Because of the nature of an MR head, it is difficult to supply constant power to the RMR of the MR head. While it may be possible to supply constant current to the RMR, constant current does not necessarily ensure constant power.
One solution involves implementing a multiplier to multiply current of the RMR (Irmr) by voltage of the RMR (Vrmr). However, multipliers are generally difficult to implement with accuracy and stability, particularly at low cost.